From 5816339310b2d9623cf413d33e538b45e815da5d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 7 May 2008 02:24:28 -0700 Subject: sparc: Fix mmap VA span checking. We should not conditionalize VA range checks on MAP_FIXED. Signed-off-by: David S. Miller --- arch/sparc/kernel/sys_sparc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/sys_sparc.c b/arch/sparc/kernel/sys_sparc.c index f188b5dc9fd0..e995491c4436 100644 --- a/arch/sparc/kernel/sys_sparc.c +++ b/arch/sparc/kernel/sys_sparc.c @@ -223,8 +223,7 @@ int sparc_mmap_check(unsigned long addr, unsigned long len, unsigned long flags) { if (ARCH_SUN4C_SUN4 && (len > 0x20000000 || - ((flags & MAP_FIXED) && - addr < 0xe0000000 && addr + len > 0x20000000))) + (addr < 0xe0000000 && addr + len > 0x20000000))) return -EINVAL; /* See asm-sparc/uaccess.h */ -- cgit v1.2.2 From 1e38c126c9252b612697e34f43b1b3371c8ee31d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 7 May 2008 16:21:28 -0700 Subject: sparc: Fix fork/clone/vfork system call restart. We clobber %i1 as well as %i0 for these system calls, because they give two return values. Therefore, on error, we have to restore %i1 properly or else the restart explodes since it uses the wrong arguments. This fixes glibc's nptl/tst-eintr1.c testcase. Signed-off-by: David S. Miller --- arch/sparc/kernel/process.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c index e7f35198ae34..36431f377dee 100644 --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -419,14 +419,26 @@ asmlinkage int sparc_do_fork(unsigned long clone_flags, unsigned long stack_size) { unsigned long parent_tid_ptr, child_tid_ptr; + unsigned long orig_i1 = regs->u_regs[UREG_I1]; + long ret; parent_tid_ptr = regs->u_regs[UREG_I2]; child_tid_ptr = regs->u_regs[UREG_I4]; - return do_fork(clone_flags, stack_start, - regs, stack_size, - (int __user *) parent_tid_ptr, - (int __user *) child_tid_ptr); + ret = do_fork(clone_flags, stack_start, + regs, stack_size, + (int __user *) parent_tid_ptr, + (int __user *) child_tid_ptr); + + /* If we get an error and potentially restart the system + * call, we're screwed because copy_thread() clobbered + * the parent's %o1. So detect that case and restore it + * here. + */ + if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK) + regs->u_regs[UREG_I1] = orig_i1; + + return ret; } /* Copy a Sparc thread. The fork() return value conventions -- cgit v1.2.2 From dc5dc7e6d71ca9fd1ea01a1418150af3b2937489 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 7 May 2008 18:54:05 -0700 Subject: sparc: Fix SA_ONSTACK signal handling. We need to be more liberal about the alignment of the buffer given to us by sigaltstack(). The user should not need to be mindful of all of the alignment constraints we have for the stack frame. This mirrors how we handle this situation in clone() as well. Also, we align the stack even in non-SA_ONSTACK cases so that signals due to bad stack alignment can be delivered properly. This makes such errors easier to debug and recover from. Finally, add the sanity check x86 has to make sure we won't overflow the signal stack. This fixes glibc testcases nptl/tst-cancel20.c and nptl/tst-cancelx20.c Signed-off-by: David S. Miller --- arch/sparc/kernel/signal.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/signal.c b/arch/sparc/kernel/signal.c index 3c312290c3c2..368157926d24 100644 --- a/arch/sparc/kernel/signal.c +++ b/arch/sparc/kernel/signal.c @@ -245,15 +245,29 @@ static inline int invalid_frame_pointer(void __user *fp, int fplen) static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize) { - unsigned long sp; + unsigned long sp = regs->u_regs[UREG_FP]; - sp = regs->u_regs[UREG_FP]; + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user *) -1L; /* This is the X/Open sanctioned signal stack switching. */ if (sa->sa_flags & SA_ONSTACK) { - if (!on_sig_stack(sp) && !((current->sas_ss_sp + current->sas_ss_size) & 7)) + if (sas_ss_flags(sp) == 0) sp = current->sas_ss_sp + current->sas_ss_size; } + + /* Always align the stack frame. This handles two cases. First, + * sigaltstack need not be mindful of platform specific stack + * alignment. Second, if we took this signal because the stack + * is not aligned properly, we'd like to take the signal cleanly + * and report that. + */ + sp &= ~7UL; + return (void __user *)(sp - framesize); } -- cgit v1.2.2 From c07c6053c41f736711ed856aa377007078c7c396 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sat, 10 May 2008 00:31:28 -0700 Subject: sparc32: Don't twiddle PT_DTRACE in exec. That bit isn't used on this platform. Signed-off-by: David S. Miller --- arch/sparc/kernel/process.c | 5 ----- 1 file changed, 5 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/process.c b/arch/sparc/kernel/process.c index 36431f377dee..da48d248cc17 100644 --- a/arch/sparc/kernel/process.c +++ b/arch/sparc/kernel/process.c @@ -638,11 +638,6 @@ asmlinkage int sparc_execve(struct pt_regs *regs) (char __user * __user *)regs->u_regs[base + UREG_I2], regs); putname(filename); - if (error == 0) { - task_lock(current); - current->ptrace &= ~PT_DTRACE; - task_unlock(current); - } out: return error; } -- cgit v1.2.2 From 986bef854fab44012df678a5b51817d5274d3ca1 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sat, 10 May 2008 21:11:23 -0700 Subject: sparc: Fix ptrace() detach. Forever we had a PTRACE_SUNOS_DETACH which was unconditionally recognized, regardless of the personality of the process. Unfortunately, this value is what ended up in the GLIBC sys/ptrace.h header file on sparc as PTRACE_DETACH and PT_DETACH. So continue to recognize this old value. Luckily, it doesn't conflict with anything we actually care about. Signed-off-by: David S. Miller --- arch/sparc/kernel/ptrace.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/ptrace.c b/arch/sparc/kernel/ptrace.c index 7f44ae69b29e..60dfc65549db 100644 --- a/arch/sparc/kernel/ptrace.c +++ b/arch/sparc/kernel/ptrace.c @@ -441,6 +441,8 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) break; default: + if (request == PTRACE_SPARC_DETACH) + request = PTRACE_DETACH; ret = ptrace_request(child, request, addr, data); break; } -- cgit v1.2.2 From 28e6103665301ce60634e8a77f0b657c6cc099de Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sun, 11 May 2008 02:07:19 -0700 Subject: sparc: Fix debugger syscall restart interactions. So, forever, we've had this ptrace_signal_deliver implementation which tries to handle all of the nasties that can occur when the debugger looks at a process about to take a signal. It's meant to address all of these issues inside of the kernel so that the debugger need not be mindful of such things. Problem is, this doesn't work. The idea was that we should do the syscall restart business first, so that the debugger captures that state. Otherwise, if the debugger for example saves the child's state, makes the child execute something else, then restores the saved state, we won't handle the syscall restart properly because we lose the "we're in a syscall" state. The code here worked for most cases, but if the debugger actually passes the signal through to the child unaltered, it's possible that we would do a syscall restart when we shouldn't have. In particular this breaks the case of debugging a process under a gdb which is being debugged by yet another gdb. gdb uses sigsuspend to wait for SIGCHLD of the inferior, but if gdb itself is being debugged by a top-level gdb we get a ptrace_stop(). The top-level gdb does a PTRACE_CONT with SIGCHLD to let the inferior gdb see the signal. But ptrace_signal_deliver() assumed the debugger would cancel out the signal and therefore did a syscall restart, because the return error was ERESTARTNOHAND. Fix this by simply making ptrace_signal_deliver() a nop, and providing a way for the debugger to control system call restarting properly: 1) Report a "in syscall" software bit in regs->{tstate,psr}. It is set early on in trap entry to a system call and is fully visible to the debugger via ptrace() and regsets. 2) Test this bit right before doing a syscall restart. We have to do a final recheck right after get_signal_to_deliver() in case the debugger cleared the bit during ptrace_stop(). 3) Clear the bit in trap return so we don't accidently try to set that bit in the real register. As a result we also get a ptrace_{is,clear}_syscall() for sparc32 just like sparc64 has. M68K has this same exact bug, and is now the only other user of the ptrace_signal_deliver hook. It needs to be fixed in the same exact way as sparc. Signed-off-by: David S. Miller --- arch/sparc/kernel/entry.S | 2 ++ arch/sparc/kernel/ptrace.c | 4 +-- arch/sparc/kernel/rtrap.S | 11 +++++--- arch/sparc/kernel/signal.c | 64 ++++++++++++++++++++-------------------------- 4 files changed, 40 insertions(+), 41 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S index 57d1bbdd0bd2..4bcfe54f878d 100644 --- a/arch/sparc/kernel/entry.S +++ b/arch/sparc/kernel/entry.S @@ -1306,6 +1306,8 @@ ret_from_fork: .align 4 .globl linux_sparc_syscall linux_sparc_syscall: + sethi %hi(PSR_SYSCALL), %l4 + or %l0, %l4, %l0 /* Direct access to user regs, must faster. */ cmp %g1, NR_SYSCALLS bgeu linux_sparc_ni_syscall diff --git a/arch/sparc/kernel/ptrace.c b/arch/sparc/kernel/ptrace.c index 60dfc65549db..81f3b929743f 100644 --- a/arch/sparc/kernel/ptrace.c +++ b/arch/sparc/kernel/ptrace.c @@ -170,8 +170,8 @@ static int genregs32_set(struct task_struct *target, switch (pos) { case 32: /* PSR */ psr = regs->psr; - psr &= ~PSR_ICC; - psr |= (reg & PSR_ICC); + psr &= ~(PSR_ICC | PSR_SYSCALL); + psr |= (reg & (PSR_ICC | PSR_SYSCALL)); regs->psr = psr; break; case 33: /* PC */ diff --git a/arch/sparc/kernel/rtrap.S b/arch/sparc/kernel/rtrap.S index 77ca6fd81253..b27b5b56f77a 100644 --- a/arch/sparc/kernel/rtrap.S +++ b/arch/sparc/kernel/rtrap.S @@ -50,8 +50,9 @@ rtrap_7win_patch5: and %g1, 0x7f, %g1 ret_trap_entry: ret_trap_lockless_ipi: andcc %t_psr, PSR_PS, %g0 + sethi %hi(PSR_SYSCALL), %g1 be 1f - nop + andn %t_psr, %g1, %t_psr wr %t_psr, 0x0, %psr b ret_trap_kernel @@ -73,7 +74,6 @@ signal_p: ld [%sp + STACKFRAME_SZ + PT_PSR], %t_psr mov %l5, %o1 - mov %l6, %o2 call do_signal add %sp, STACKFRAME_SZ, %o0 ! pt_regs ptr @@ -81,6 +81,8 @@ signal_p: ld [%sp + STACKFRAME_SZ + PT_PSR], %t_psr clr %l6 ret_trap_continue: + sethi %hi(PSR_SYSCALL), %g1 + andn %t_psr, %g1, %t_psr wr %t_psr, 0x0, %psr WRITE_PAUSE @@ -137,8 +139,9 @@ ret_trap_userwins_ok: LOAD_PT_PRIV(sp, t_psr, t_pc, t_npc) or %t_pc, %t_npc, %g2 andcc %g2, 0x3, %g0 + sethi %hi(PSR_SYCALL), %g2 be 1f - nop + andn %t_psr, %g2, %t_psr b ret_trap_unaligned_pc add %sp, STACKFRAME_SZ, %o0 @@ -201,6 +204,8 @@ rtrap_patch5: and %g1, 0xff, %g1 1: LOAD_PT_ALL(sp, t_psr, t_pc, t_npc, g1) 2: + sethi %hi(PSR_SYSCALL), %twin_tmp1 + andn %t_psr, %twin_tmp1, %t_psr wr %t_psr, 0x0, %psr WRITE_PAUSE diff --git a/arch/sparc/kernel/signal.c b/arch/sparc/kernel/signal.c index 368157926d24..3fd1df9f9ba7 100644 --- a/arch/sparc/kernel/signal.c +++ b/arch/sparc/kernel/signal.c @@ -145,6 +145,9 @@ asmlinkage void do_sigreturn(struct pt_regs *regs) regs->psr = (up_psr & ~(PSR_ICC | PSR_EF)) | (regs->psr & (PSR_ICC | PSR_EF)); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) @@ -199,6 +202,9 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs) regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) @@ -507,26 +513,36 @@ static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ -asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0, int restart_syscall) +asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0) { - siginfo_t info; - struct sparc_deliver_cookie cookie; struct k_sigaction ka; - int signr; + int restart_syscall; sigset_t *oldset; + siginfo_t info; + int signr; - cookie.restart_syscall = restart_syscall; - cookie.orig_i0 = orig_i0; + if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) + restart_syscall = 1; + else + restart_syscall = 0; if (test_thread_flag(TIF_RESTORE_SIGMASK)) oldset = ¤t->saved_sigmask; else oldset = ¤t->blocked; - signr = get_signal_to_deliver(&info, &ka, regs, &cookie); + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + + /* If the debugger messes with the program counter, it clears + * the software "in syscall" bit, directing us to not perform + * a syscall restart. + */ + if (restart_syscall && !pt_regs_is_syscall(regs)) + restart_syscall = 0; + if (signr > 0) { - if (cookie.restart_syscall) - syscall_restart(cookie.orig_i0, regs, &ka.sa); + if (restart_syscall) + syscall_restart(orig_i0, regs, &ka.sa); handle_signal(signr, &ka, &info, oldset, regs); /* a signal was successfully delivered; the saved @@ -538,16 +554,16 @@ asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0, int rest clear_thread_flag(TIF_RESTORE_SIGMASK); return; } - if (cookie.restart_syscall && + if (restart_syscall && (regs->u_regs[UREG_I0] == ERESTARTNOHAND || regs->u_regs[UREG_I0] == ERESTARTSYS || regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { /* replay the system call when we are done */ - regs->u_regs[UREG_I0] = cookie.orig_i0; + regs->u_regs[UREG_I0] = orig_i0; regs->pc -= 4; regs->npc -= 4; } - if (cookie.restart_syscall && + if (restart_syscall && regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { regs->u_regs[UREG_G1] = __NR_restart_syscall; regs->pc -= 4; @@ -599,27 +615,3 @@ do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr, out: return ret; } - -void ptrace_signal_deliver(struct pt_regs *regs, void *cookie) -{ - struct sparc_deliver_cookie *cp = cookie; - - if (cp->restart_syscall && - (regs->u_regs[UREG_I0] == ERESTARTNOHAND || - regs->u_regs[UREG_I0] == ERESTARTSYS || - regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { - /* replay the system call when we are done */ - regs->u_regs[UREG_I0] = cp->orig_i0; - regs->pc -= 4; - regs->npc -= 4; - cp->restart_syscall = 0; - } - - if (cp->restart_syscall && - regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { - regs->u_regs[UREG_G1] = __NR_restart_syscall; - regs->pc -= 4; - regs->npc -= 4; - cp->restart_syscall = 0; - } -} -- cgit v1.2.2 From 8bf3028ede10dfe22e1729ebad96f6eb77020712 Mon Sep 17 00:00:00 2001 From: Robert Reif Date: Sun, 11 May 2008 18:05:20 -0700 Subject: sparc32: fix rtrap.S typo Fix compile problem in rtrap.S arch/sparc/kernel/built-in.o: In function `ret_trap_userwins_ok': arch/sparc/kernel/rtrap.S:(.text+0x1900): undefined reference to `PSR_SYCALL' Signed-off-by: Robert Reif Signed-off-by: David S. Miller --- arch/sparc/kernel/rtrap.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/rtrap.S b/arch/sparc/kernel/rtrap.S index b27b5b56f77a..ab818cdc4cc0 100644 --- a/arch/sparc/kernel/rtrap.S +++ b/arch/sparc/kernel/rtrap.S @@ -139,7 +139,7 @@ ret_trap_userwins_ok: LOAD_PT_PRIV(sp, t_psr, t_pc, t_npc) or %t_pc, %t_npc, %g2 andcc %g2, 0x3, %g0 - sethi %hi(PSR_SYCALL), %g2 + sethi %hi(PSR_SYSCALL), %g2 be 1f andn %t_psr, %g2, %t_psr -- cgit v1.2.2 From 94d149c34cda933ff5096aca94bb23bf68602f4e Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 12 May 2008 16:33:33 -0700 Subject: sparc: Fix mremap address range validation. Just like mmap, we need to validate address ranges regardless of MAP_FIXED. sparc{,64}_mmap_check()'s flag argument is unused, remove. Based upon a report and preliminary patch by Jan Lieskovsky Signed-off-by: David S. Miller --- arch/sparc/kernel/sys_sparc.c | 48 +++++-------------------------------------- 1 file changed, 5 insertions(+), 43 deletions(-) (limited to 'arch/sparc/kernel') diff --git a/arch/sparc/kernel/sys_sparc.c b/arch/sparc/kernel/sys_sparc.c index e995491c4436..3c6b49a53ae8 100644 --- a/arch/sparc/kernel/sys_sparc.c +++ b/arch/sparc/kernel/sys_sparc.c @@ -219,7 +219,7 @@ out: return err; } -int sparc_mmap_check(unsigned long addr, unsigned long len, unsigned long flags) +int sparc_mmap_check(unsigned long addr, unsigned long len) { if (ARCH_SUN4C_SUN4 && (len > 0x20000000 || @@ -295,52 +295,14 @@ asmlinkage unsigned long sparc_mremap(unsigned long addr, unsigned long old_len, unsigned long new_len, unsigned long flags, unsigned long new_addr) { - struct vm_area_struct *vma; unsigned long ret = -EINVAL; - if (ARCH_SUN4C_SUN4) { - if (old_len > 0x20000000 || new_len > 0x20000000) - goto out; - if (addr < 0xe0000000 && addr + old_len > 0x20000000) - goto out; - } - if (old_len > TASK_SIZE - PAGE_SIZE || - new_len > TASK_SIZE - PAGE_SIZE) + + if (unlikely(sparc_mmap_check(addr, old_len))) + goto out; + if (unlikely(sparc_mmap_check(new_addr, new_len))) goto out; down_write(¤t->mm->mmap_sem); - if (flags & MREMAP_FIXED) { - if (ARCH_SUN4C_SUN4 && - new_addr < 0xe0000000 && - new_addr + new_len > 0x20000000) - goto out_sem; - if (new_addr + new_len > TASK_SIZE - PAGE_SIZE) - goto out_sem; - } else if ((ARCH_SUN4C_SUN4 && addr < 0xe0000000 && - addr + new_len > 0x20000000) || - addr + new_len > TASK_SIZE - PAGE_SIZE) { - unsigned long map_flags = 0; - struct file *file = NULL; - - ret = -ENOMEM; - if (!(flags & MREMAP_MAYMOVE)) - goto out_sem; - - vma = find_vma(current->mm, addr); - if (vma) { - if (vma->vm_flags & VM_SHARED) - map_flags |= MAP_SHARED; - file = vma->vm_file; - } - - new_addr = get_unmapped_area(file, addr, new_len, - vma ? vma->vm_pgoff : 0, - map_flags); - ret = new_addr; - if (new_addr & ~PAGE_MASK) - goto out_sem; - flags |= MREMAP_FIXED; - } ret = do_mremap(addr, old_len, new_len, flags, new_addr); -out_sem: up_write(¤t->mm->mmap_sem); out: return ret; -- cgit v1.2.2